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Aqueous extract of Kalanchoe pinnata (Kp) have been found effective in models to reduce acute anaphylactic reactions. In the present study, we investigate the effect of Kp and the flavonoid quercetin (QE) and quercitrin (QI) on mast cell activation in vitro and in a model of allergic airway disease in vivo. Treatment with Kp and QE in vitro inhibited degranulation and cytokine production of bone marrow-derived mast cells following IgE/FcRI crosslinking, whereas treatment with QI had no effect. Similarly, in vivo treatment with Kp and QE decreased development of airway hyperresponsiveness, airway inflammation, goblet cell metaplasia and production of IL-5, IL-13 and TNF. In contrast, treatment with QI had no effect on these parameters. These findings demonstrate that treatment with Kp or QE is effective in treatment of allergic airway disease, providing new insights to the immunomodulatory functions of this plant. [ABSTRACT FROM AUTHOR]

Tuberculosis (TB) is a world health challenge the treatment of which is impacted by the rise of drug-resistant strains. Thus, there is an urgent need for new antitubercular compounds and novel approaches to improve current TB therapy. The zebrafish animal model has become increasingly relevant as an experimental system. It has proven particularly useful during early development for aiding TB drug discovery, supporting both the discovery of new insights into mycobacterial pathogenesis and the evaluation of therapeutical toxicity and efficacy in vivo. In this review, we summarize the past two decades of zebrafish-Mycobacterium marinum research and discuss its contribution to the field of bioactive antituberculosis therapy development., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Objectives: This work investigated the acute antinociceptive effect of a synthetic chalcone, 4-dimethylamino chalcone (DMAC), as well as its effects on vincristine-induced peripheral neuropathy (VIPN) in mice., Methods: The inhibitory activity of myeloperoxidase was assessed by measuring HOCl formation. Formalin and hot plate tests were used to study the acute antinociceptive effect of DMAC. VIPN was induced through the administration of vincristine sulphate (0.1 mg/kg, i.p., 14 days). Then, DMSO, DMAC (10 or 30 mg/kg; i.p.), or pregabalin (10 mg/kg, i.p.) were administered for 14 consecutive days. Thermal hyperalgesia and mechanical allodynia were evaluated before and after VIPN induction and on days 1, 3, 7, and 14 of treatment. Neurodegeneration and neuroinflammation were assessed through immunohistochemistry for NF200, iNOS, and arginase-1 within the sciatic nerve., Key Findings: DMAC inhibited myeloperoxidase activity in vitro and presented an acute antinociceptive effect in both formalin and hot plate tests, with the involvement of muscarinic and opioid receptors. Treatment with 30 mg/kg of DMAC significantly attenuated thermal hyperalgesia and mechanical allodynia and prevented macrophage proinflammatory polarisation in VIPN mice., Conclusions: Our results show that DMAC, acting through different mechanisms, effectively attenuates VIPN., (© The Author(s) 2024. Published by Oxford University Press on behalf of the Royal Pharmaceutical Society. All rights reserved. For commercial re-use, please contact reprints@oup.com for reprints and translation rights for reprints. All other permissions can be obtained through our RightsLink service via the Permissions link on the article page on our site—for further information please contact journals.permissions@oup.com.)

Piper aduncum L. is widely distributed in tropical regions and the ethnobotanical uses of this species encompass medicinal applications for the treatment of respiratory, antimicrobial, and gynecological diseases. Chemical studies reveal a diverse array of secondary metabolites, including terpenes, flavonoids, and prenylated compounds. Extracts from P. aduncum have shown antibacterial, antifungal, and larvicidal activities. Our study explores the activity of extracts and partitions against Mycobacterium tuberculosis H37Rv, as well as the chemical diversity of the bioactive partition. This marks the first investigation of the bioactive partition of P. aduncum from agroecological cultivation. The ethyl acetate partition from the ethanolic leaf extract (PAEPL) was found to be the most active. PAEPL was subjected to column chromatography using Sephadex LH-20 and the obtained fractions were analyzed using UHPLC-HRMS/MS. The MS/MS data from the fractions were submitted to the online GNPS platform for the generation of the molecular network, which displayed 1714 nodes and 167 clusters. Compounds were identified via manual inspection and different libraries, allowing the annotation of 83 compounds, including flavonoids, benzoic acid derivatives, glycosides, free fatty acids, and glycerol-esterified fatty acids. This study provides the first chemical fingerprint of an antimycobacterial sample from P. aduncum cultivated in an agroecological system.

Inga laurina is a plant species which produces edible fruits, and until now there is little information available concerning its nutritional, chemical and bioactive composition. In this study, we evaluated for the first time the proximate composition and mineral contents in its fruit (peel, pulp and seed), that is the traditionally consumed part. The seeds obtained the highest protein (19.52 g/100 g), carbohydrate (22.5 g/100 g) and mineral contents, mainly Cu, Cr, P, Mn, Se and Zn. The peel and pulp were excellent sources of fiber (4.5 and 11.05 g/100 g) as well as mineral content, with Cr and Cu standing out in the pulp. This study is notably the first to provide a detailed assessment of the nutritional compositions of traditionally consumed and not consumed parts of this fruit. Sensory analysis of the pulp was also performed, which indicated good acceptance. The antioxidant properties were characterized in the fruit, peels and leaves. The ABTS test showed that leaf supernatant hydroethanolic crude extract (EC 50  = 2.70 μg/mL) and its corresponding ethyl acetate (EC 50  = 1.68 µg/mL) and butanol (EC 50  = 2.48 µg/mL) partitions presented higher antioxidant potential compared to the control Ginkgo biloba (EC 50  = 12.17 µg/mL). The most active precipitate extract regarding DPPH was from the peel (EC 50  = 13.30 μg /mL) and the most active partition was the ethyl acetate (EC 50  = 13.37 μg/mL), both with better activity compared to the control Ginkgo biloba (EC 50  = 46.97 μg/mL). The ethyl acetate partition (EC 50  = 13.45 μg/mL) and butanol partition (EC 50  = 7.97 μg/mL) from the leaves showed the highest antioxidant capacity. Thus, extracts and partitions from the peels and leaves were studied from a phytochemical point of view due to presenting the best results for antioxidant capacity. The presence of phenolic compounds such as myricetin-3-O-rhamnopyranoside, myricetin-3-O-(2″-O-galloyl)-rhamnopyranoside and myricetin-3-O-(2″,4″-di-O-galloyl)-arabinopentoside-methyl ether were observed in the leaf crude extract and polar partitions, being reported for the first time in the Inga genus and Fabaceae family. Moreover, quercetin, quercetin-3-O-galatoctoside, quercetin-3-O-rhamnopyranoside, quercetin-3-O-(2″-O-galloyl)-rhamnoside, and quercetin tri-hexose were identified in the peel crude extract and ethyl acetate partition, in which the galloyl derivative of quercetin was identified for the first time in I. laurina fruit peels. GC-MS enabled separating and identifying substances such as palmitic and stearic acids, and ethyl oleate. It is possible to conclude that I. laurina pulp can be a supplementary food as a source of phenolic compounds, and the other organs of the plant (leaves and peel) are rich in flavonoids with great antioxidant capacity, making this species a promising source of antioxidants., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

Antifungal resistance poses a significant challenge to disease management, necessitating the development of novel drugs. Antimicrobial peptides offer potential solutions. This study focused on extraction and characterization of peptides from Adenanthera pavonina seeds with activity against Candida species, Mycobacterium tuberculosis, proteases, and α-amylases. Peptides were extracted in phosphate buffer and heated at 90°C for 10 min to create a peptide rich heated fraction (PRHF). After confirming antimicrobial activity and the presence of peptides, the PRHF underwent ion exchange chromatography, yielding retained and non-retained fractions. These fractions were evaluated for antimicrobial activity and cytotoxicity against murine macrophages. The least toxic and most active fraction underwent reversed-phase chromatography, resulting in ten fractions. These fractions were tested for peptides and antimicrobial activity. The most active fraction was rechromatographed on a reversed-phase column, resulting in two fractions that were assessed for antimicrobial activity. The most active fraction revealed a single band of approximately 6 kDa and was tested for inhibitory effects on proteases and α-amylases. Thermal stability experiments were conducted on the 6 kDa peptide at different temperatures followed by reassessment of antifungal activity and circular dichroism. The 6 kDa peptide inhibited yeasts, M. tuberculosis, human salivary and Tenebrio molitor larvae intestine α-amylases, and proteolytic activity from fungal extracts, and thus named ApPI. Remarkably, ApPI retained antifungal activity and conformation after heating and is primarily composed of α-helices. ApPI is a thermally stable serine protease/α-amylase inhibitor from A. pavonina seeds, offering promise as a foundational molecule for innovative therapeutic agents against fungal infections and tuberculosis., (© 2023. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

Six previously undescribed intact limonoids together with four known compounds were isolated from the seeds of Trichilia lepidota subsp. schumanniana (Harms) T.D.Penn. Their structures were characterized based on one- and two-dimensional nuclear magnetic resonance spectra, infrared, ultraviolet, mass spectroscopy results, and optical rotation. All compounds were evaluated for their ability to inhibit nitric oxide production in cultures of RAW 264.7 macrophages stimulated by lipopolysaccharide, cytotoxicity and growth of Mycobacterium tuberculosis strains H37Rv and M299. The compounds 7-deacetyl-11β,12α-diacetoxy-14,15-epoxyazadirone (5) and walsurin E (9) were the most potent in inhibiting nitric oxide production, although the compounds 1-deshydroxy-12α-acetoxymunronin N (1) and 6α,12α-dihydroxyazadirone (6) also showed controlled potential of this mediator, in addition to being potent growth inhibitors of Mycobacterium tuberculosis H37RV and M299, without cytotoxicity interference. Ring intact limonoids isolated from Trichilia lepidota subsp. schumanniana seeds are a new source of bioactive substances that may be used in the future against diseases such as tuberculosis and other processes related to inflammation., Competing Interests: Declaration of competing interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Ivo J. Curcino Vieira reports financial support was provided by Carlos Chagas Filho Foundation for Research Support of Rio de Janeiro State. Ivo J. Curcino Vieira reports financial support was provided by National Council for Scientific and Technological Development. Raimundo Braz-Filho, Renata Rodrigues da Silva Robaina reports financial support was provided by Carlos Chagas Filho Foundation for Research Support of Rio de Janeiro State. Raimundo Braz-Filho reports financial support was provided by National Council for Scientific and Technological Development. Michel de Souza Passos, Thalya Soares Ribeiro Nogueira reports financial support was provided by Coordination of Higher Education Personnel Improvement., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

The guava tree ( Psidium guajava ) is a tropical species native to South America and is recognized as the 11th most economically important fruit tree in Brazil. However, the presence of the nematode Meloidogyne enterolobii and the fungus Fusarium solani in the roots of guava plants leads to the development of root galls, causing significant damage. In contrast, the species P. guineense and P. cattleianum have been identified as resistant and immune to the nematode, respectively. In this study, the researchers aimed to compare the metabolomic profiles of infected and uninfected roots of P. guajava , P. cattleianum , and P. guineense using mass spectrometry coupled with liquid chromatography (LC-MS). The goal was to identify secondary metabolites that could potentially be utilized as biochemical resources for nematode control. The findings of the study demonstrated that the plant metabolism of all three species undergoes alterations in response to the phytopathogen inoculation. By employing molecular networks, the researchers identified that the secondary metabolites affected by the infection, whether produced or suppressed, are primarily of a polar chemical nature. Further analysis of the database confirmed the polar nature of the regulated substances after infection, specifically hydrolysable tannins and lignans in P. guineense and P. cattleianum . Interestingly, a group of non-polar substances belonging to the terpene class was also identified in the resistant and immune species. This suggests that these terpenes may act as inhibitors of M. enterolobii , working as repellents or as molecules that can reduce oxidative stress during the infection process, thus enhancing the guava resistance to the nematode. Overall, this study provides valuable insights into the metabolic alterations occurring in different Psidium spp. in response to M. enterolobii infection. The identification of specific secondary metabolites, particularly terpenes, opens up new possibilities for developing effective strategies to control the nematode and enhance guava resistance., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2023 The Authors.)

This study evaluated the analgesic and anti-inflammatory activities of Vitex polygama . Ethyl acetate and butanol fractions (10-30 mg/kg), obtained from the hydroalcoholic leaf extract, showed an antinociceptive effect in the acetic acid-induced abdominal writhing test, formalin test and modified hot plate test in mice, indicating a peripheral anti-inflammatory action. Ethyl acetate and butanol fractions were effective in inhibiting nitric oxide and TNF-α production, respectively, in RAW 264.7 macrophages. Both fractions (10-30 mg/kg) showed an acute analgesic effect in mice with vincristine-induced neuropathic pain exposed to a thermal stimulus. Through ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-UV-MS/MS) it was possible to identify seven major compounds: isoorientin, orientin, vitexin, isovitexin, O - p -hydroxybenzoyl orientin, O -caffeoyl-orientin, and di-caffeoylquinic acid. Orientin and isoorientin were isolated from ethyl acetate fraction and had their identity confirmed by nuclear magnetic resonance (NMR). Glucosyl flavones appear to be the main metabolites responsible for the anti-inflammatory and analgesic activities observed for V. polygama .

Background: Antimicrobial peptides, natural or synthetic, appear as promising molecules for antimicrobial therapy because of their both broad antimicrobial activity and mechanism of action. Herein, we determine the anti-Candida and antimycobacterial activities, mechanism of action on yeasts, and cytotoxicity on mammalian cells in the presence of the bioinspired peptide CaDef2.1 G27-K44 ., Methods: CaDef2.1 G27-K44 was designed to attain the following criteria: high positive net charge; low molecular weight (<3000 Da); Boman index ≤2.5; and total hydrophobic ratio ≥ 40%. The mechanism of action was studied by growth inhibition, plasma membrane permeabilization, ROS induction, mitochondrial functionality, and metacaspase activity assays. The cytotoxicity on macrophages, monocytes, and erythrocytes were also determined., Results: CaDef2.1 G27-K44 showed inhibitory activity against Candida spp. with MIC 100 values ranging from 25 to 50 μM and the standard and clinical isolate of Mycobacterium tuberculosis with MIC 50 of 33.2 and 55.4 μM, respectively. We demonstrate that CaDef2.1 G27-K44 is active against yeasts at different salt concentrations, induced morphological alterations, caused membrane permeabilization, increased ROS, causes loss of mitochondrial functionality, and activation of metacaspases. CaDef2.1 G27-K44 has low cytotoxicity against mammalian cells., Conclusions: The results obtained showed that CaDef2.1 G27-K44 has great antimicrobial activity against Candida spp. and M. tuberculosis with low toxicity to host cells. For Candida spp., the treatment with CaDef2.1 G27-K44 induces a process of regulated cell death with apoptosis-like features., General Significance: We show a new AMP bioinspired with physicochemical characteristics important for selectivity and antimicrobial activity, which is a promising candidate for drug development, mainly to control Candida infections., (Copyright © 2022 Elsevier B.V. All rights reserved.)

Tuberculosis remains a major health problem worldwide. Drug-resistant and hypervirulent Mycobacterium tuberculosis (Mtb) strains can lead to a hyperinflammatory response and necrotic pathology in hyper-reactive individuals that require adjunctive treatment. Plant-derived substances have been investigated for TB treatment, among which flavonoids stand out. We evaluate the anti-Mtb, anti-inflammatory and cytotoxicity activities of fractions and substances 1, 2 and 3 isolated from Erythrina verna through a bioassay guided fractionation. Seven fractions (1, 3-5 and 7-9) obtained from dichloromethane E. verna extract inhibited NO production (IC50 ≤ 15 μg/mL) with none or poor cytotoxic effect, while the fractions 4 and 5 notably reduced TNF-a production. Fractions 4, 6 and 9 suppressed Mycobacterium growth with MIC50 ≤ 20 μg/mL. Fraction 4 was the most potent due to dual biological activities. Erythratidinone and alpinumisoflavone inhibited the growth of Mtb H37Rv and hypervirulent strain in bacterial cultures (MIC50 ≤ 20 μg/mL), with erythratidinone standing out in reducing intracellular growth of Mtb H37Rv (5.8 ± 1.1 μg/mL). Alpinumisoflavone and erythratidinone were capable of inhibiting NO and TNF-α production besides showing significant inhibitory effects against Mycobacterium tuberculosis strains with low toxicity in macrophages. Both substances are promising for further studies focusing on an anti-TB dual treatment approach.

Chalcones (1,3-diphenylpropen-1-ones) are a class of flavonoids that have been shown a broad spectrum of biological activities with therapeutic potential. Naturally occurring chalcones or synthetic chalcone derivatives have been extensively investigated as anticancer compounds. Cancer is still among the leading causes of death globally, although cancer treatments have improved over the past decades. Most of chemotherapeutic drugs target proliferating tumor cells; however, the cancer cells capabilities are also associated to tumor surround microenvironment. Thereby, the search of new compounds with a broad antitumor activity is still a great challenge. The cytotoxicity mechanisms of chalcones are beyond apoptosis induction in tumor cells, which make them promising compound for cancer therapy. In this mini-review we summarized recent studies that describe the anticancer potential of chalcones related to some of hallmarks of cancer. We shed a light on sustaining proliferative signaling, tumor-promoting inflammation, activating invasion and metastasis, inducing angiogenesis and resisting cell death.

Objectives: This study aimed to evaluate endophytic fungi isolated from Tocoyena bullata and Humiria balsamifera plant species for their antimycobacterial and anti-inflammatory activities, focusing on severe pulmonary tuberculosis cases which are often associated with exacerbated inflammation., Methods: Mycobacterium suspensions were incubated with the samples for 5 days. RAW 264.7 macrophages stimulated with LPS were also incubated with them for 24 h to assess the inhibition of inflammatory mediator production and cytotoxicity. C57BL/6 mice were infected with Mtb M299 and treated for 15 days with lasiodiplodin (Lasio)., Key Findings: Endophytic fungus Sordaria tamaensis, obtained from T. bullata, was the most promising. Its ethanolic extract impaired mycobacterial growth with MIC50 (µg/ml): 1.5 ± 0.6 (BCG), 66.8 ± 0.1 (H37Rv) and 80.0 ± 0.1 (M299). (R)-(+)-Lasio showed MIC50 92.2 ± 1.8 µg/ml (M299). In addition, Lasio was able to inhibit NO, IL-1β and TNF-α production and was not cytotoxic for macrophages. M. tuberculosis-infected C57BL/6 animals treated by Lasio reduced the number of acid-fast bacilli, lung pathology, leucocyte influx and proinflammatory cytokine production in the lungs. The class IIa fructose 1,6-bisphosphate aldolase was the predicted hypothetical target of Lasio., Conclusions: (R)-(+)-Lasio stood out as a promising anti-TB compound, exhibiting anti-inflammatory and antimycobacterial effects, as well as low cytotoxicity., (© The Author(s) 2021. Published by Oxford University Press on behalf of the Royal Pharmaceutical Society. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Tuberculosis (TB) remains a worldwide public health threat because of the emergence of resistant strains and subsequent inappropriate response to current therapy. We have been studying the restinga plants' antimycobacterial and anti-inflammatory potential. Dichloromethane fraction (DCM) from Vitex polygama Cham. showed high activity against Mycobacterium tuberculosis (Mtb) H37Rv. In this context, DCM fraction and isolated compounds were investigated against Mtb H37Rv and M299 (MDR strain) and for their immunomodulatory and cytotoxicity actions. Orientin showed the best antimycobacterial effect against Mtb M299 MDR strain (MIC 50 15.4 ± 1.6 µg/mL), capacity of inhibiting NO production by macrophages (IC 50 6.5 ± 1.2 µg/mL) and no significant cytotoxicity. The antimycobacterial effect of orientin was also observed on Mtb H37Rv intracellular growth in RAW 264.7 macrophages (MIC 50 3.5 ± 1.1 and MIC 90 9.1 ± 1.0 µg/mL). This is the first report describing the antimycobacterial effect of orientin, in both extra- and intracellular growth.[Formula: see text].

Tuberculosis (TB) remains a serious public health problem and one of the main concern is the emergence of multidrug-resistant and extensively resistant TB. Hyper-reactive patients develop inflammatory necrotic lung lesions that aggravate the pathology and facilitate transmission of mycobacteria. Treatment of severe TB is a major clinical challenge that has few effective solutions and patients face a poor prognosis, years of treatment and different adverse drug reactions. In this work, fifteen novel and thirty-one unusual thiourea derivatives were synthesized and evaluated in vitro for their antimycobacterial and anti-inflammatory potential and, in silico for ADMET parameters and for structure-activity relationship (SAR). Thioureas derivatives 10, 15, 16, 28 and 29 that had shown low cytotoxicity and high activities were selected for further investigation, after SAR study. These five thioureas derivatives inhibited Mtb H37Rv growth in bacterial culture and in infected macrophages, highlighting thiourea derivative 28 (MIC 50 2.0 ± 1.1 and 2.3 ± 1.1 µM, respectively). Moreover, these compounds were active against the hypervirulent clinical Mtb strain M299, in bacterial culture, especially 16, 28 and 29, and in extracellular clumps, highlighting 29, with MIC 50 5.6 ± 1.2 µM. Regarding inflammation, they inhibited NO through the suppression of iNOS expression, and also inhibited the production of TNF-α and IL-1β. In silico studies were carried out suggesting that these five compounds could be administered by oral route and have low toxicological effects when compared to rifampicin. In conclusion, our data show that, at least, thiourea derivatives 16, 28 and 29 are promising antimycobacterial and anti-inflammatory agents, and candidates for further prospective studies aiming new anti-TB drugs, that can be used on a dual approach for the treatment of severe TB cases associated with exacerbated inflammation., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

The aim of this study was to perform the isolation and characterization of vasodilatory flavonoids from Tapirira guianensis Aubl. (Annacardiaceae) leaves. In this context, ethyl acetate fraction (EA fraction) was obtained and subjected to fractionation batches by HSCCC affording: myricetin 3- O - α -L-rhamnopyranoside (myricitrin, 1 ); quercetin 3- O -(6"- O -galloyl)- β -D-galactopyranoside ( 2 ); quercetin 3- O - α -L-arabinofuranoside (avicularin, 3 ); and quercetin 3- O - α -L-rhamnopyranoside (quercitrin, 4 ). Myricitrin ( 1 ) induced a relaxation of 56.07 ± 13.04% at 300 μM (P < 0.05; n = 5), indicating that this flavonoid contributes to the vasodilatory activity of EA fraction. In addition, all EA fraction flavonoids were evaluated for their capacity of inhibiting myeloperoxidase activity and flavonoid ( 2 ) (IC 50 1.0 ± 0.3 µM) was the strongest peroxidase inhibitor. In conclusion, it was possible to verify that myricitrin together with quercetin are mainly responsible for vasodilatory potential, besides flavonoid 2 for myeloperoxidase inhibition. Together these flavonoids seem to be responsible for Tapirira guianensis cardiovascular effects.

Endothelial dysfunction in obesity plays a key role in the development of cardiovascular diseases, and it is characterized by increased vascular tonus and oxidative stress. Thus, this study aimed to investigate the vasodilatory and antioxidant activities of Mandevilla moricandiana ethyl acetate fraction and subfractions. Vascular effects were investigated on aorta isolated from control and monosodium glutamate (MSG) induced-obese Wistar rats, and antioxidant activity was assessed by 2,2-diphenyl-1-picrylhydrazyl (DPPH) and oxygen radical absorbance capacity (ORAC) methods. The ethyl acetate fraction (MMEAF) induced a concentration-dependent vasodilation on aortic rings through the NO pathway, with the involvement of histamine H1 and estrogen ERα receptors and showed potent antioxidant activity. In aorta of MSG obese rats, maximal relaxation to acetylcholine was increased in the presence of MMEAF (3 µg/mL), indicating that MMEAF ameliorated obesity-induced endothelial dysfunction. Quercetin and kaempferol aglycones and their correspondent glycosides, as well as caffeoylquinic acid derivatives, A-type procyanidin trimer, ursolic and oleanolic triterpenoid acids were identified in subfractions from MMEAF and seem to be the metabolites responsible for the vascular and antioxidant activities of this fraction.

Microbial resistance to available drugs is a growing health threat imposing the need for the development of new drugs. The scaffold of plant defensins, including their γ-cores, are particularly good candidates for drug design. This work aimed to improve the antifungal activity of a previous design peptide, named A 36 , 42 , 44 γ 32-46 VuDef (for short DD) against yeasts by altering its biochemical parameters. We explore the correlation of the biological activity and structure of plant defensins and compared their primary structures by superimposition with VuDef 1 and DD which indicated us the favorable position and the amino acid to be changed. Three new peptides with modifications in charge, hydrophobicity (RR and WR) and chirality (D-RR) were designed and tested against pathogenic yeasts. Inhibition was determined by absorbance. Viability of mammalian cells was determined by MTT. The three designed peptides had better inhibitory activity against the yeasts with better potency and spectrum of yeast species inhibition, with low toxicity to mammalian cells. WR, the most hydrophobic and cationic, exhibited better antifungal activity and lower toxicity. Our study provides experimental evidence that targeted changes in the primary structure of peptides based on plant defensins γ-core primary structures prove to be a good tool for the synthesis of new compounds that may be useful as alternative antifungal drugs. The method described did not have the drawback of synthesis of several peptides, because alterations are guided. When compared to other methods, the design process described is efficient and viable to those with scarce resources.

Glycosylated flavonoids, caffeoylquinic acid and 3,5-dicaffeoylquinic acid have been identified in the ethyl acetate partition from the crude ethanol extract of Tocoyena bullata (Rubiaceae) leaves. The fraction containing the mixture of flavonol rutin and a tetraglycosylated flavonoid showed 89.2% inhibition and the mixture of isoquercitrin and 3,5-dicaffeoylquinic acid showed 88.5% inhibition of mast cell degranulation. These results demonstrated that the tetraglycosylated flavonoid, rutin, isoquercitrin and 3,5-dicaffeioylquinic acid were the most promising phenolics for inhibition of mast cell degranulation. For the first time the identification of phenolic constituents and their correlation with inhibitory effect on mast cell degranulation were reported in this work.

The specie Ocotea notata (Nees & Mart). Mez is a tree with 5 meters high, that can be found in restinga regions in the Brazilian coast. This study describes a phytochemical investigation, total phenolic content and the antioxidant activity of extracts and fractions by DPPH and ORAC. Phenolic content revealed equivalent concentration between evaluated samples, similar to found in the leave extract (66.4 mEq GA/g). By DPPH, extracts and fractions showed effective concentration (EC 50 ) lower than the standards Ginkgo biloba 761 ® (23.60 ± 0.64 µg/ml) and quercetin (6.06 ± 0, 92 µg/mL); for the ORAC method, ethyl acetate partition showed a value of 2.06 mmol Trolox equivalent g -1 better than obtained in Ginkgo biloba (1.03 ± 0.25 mmol.Trolox equivalent g -1 . The butanol partition (0.52 mmol.Trolox equivalent g -1 ) and the aqueous residue (0.74 mmol Trolox equivalent g -1 ) have a lesser ORAC potential than ethyl acetate partition. The butanolic partition, investigated by LC-DAD-MS/MS and QTOF-MS, revealed six major compounds: miquelianin (1), isoquercitrin (2), quercitrin (3), kaempferol-3- O -pentose (4), afzelin (5) and isorhamnetin-glucuronide (6).

Scientific advances have not been enough to combat the growing resistance to antimicrobial medicines. Antimicrobial peptides (AMPs) are effector molecules of the innate immune defense system in plants and could provide an important source of new antimicrobial drugs. The aim of this work was to extract, purify, characterize, and evaluate the antifungal activities present in fractions obtained from Capsicum annum fruits through reversed-phase chromatography. The fractions named F2 and F3 presented the highest inhibitory activity against Candida and Mycobacterium tuberculosis species. In addition, we identified two sequences of AMPs in the F2 and F3 fractions through mass spectrometry that showed similarity to an already well-characterized family of plant defensins. A plasma membrane permeabilization assay demonstrated that the peptides present in F2, F3, and F4 fractions induced changes in the membrane of some yeast strains, culminating in permeabilization. The production of reactive oxygen species was induced by the fractions in some yeast strains. Fractions F2, F3, and F4 also did not show toxicity in macrophage or monocyte cultures. In conclusion, the obtained data demonstrate that the AMPs, especially those present in the fractions F2 and F3, are promising antimicrobial agents that may be useful to enhance the development of new therapeutic agents for the treatment of diseases.

Ethnopharmacological Relevance: Vochysia divergens Pohl (Vochysiaceae), popularly known as "Cambará", is a tree that is resistant to the seasonal floods in the Pantanal, and usually found in monodominant stands called "Cambarazal". The inhabitants of the Pantanal exploit this tree for medicinal uses. Infusions and decoctions of its leaves are taken as teas, particularly for the treatment of asthma, flu and diarrhea, according to the local tradition transmitted empirically through the generations., Aim of the Study: To evaluate the beneficial health effects related to the ethnomedicinal uses of V. divergens (Vd) by using biomonitored fractionation of an aqueous leaf extract., Materials and Methods: The aqueous leaf extract was obtained by decoction, and then the extract was fractionated by a combination of separation techniques including precipitation, organic partition and chromatography. Chromatographic analyses of the active samples were carried out using HPLC-DAD-MS. Flavonoid 1 was isolated from the n-BuOH fraction through classic chromatographic techniques. The inhibitory effects and cytotoxicity of the Vd extract, fractions and flavonoid 1 on NO and TNF-α production were assessed in LPS-stimulated RAW 264.7 macrophage cultures. Additionally, suppression on the proliferation of BALB/c lymphocytes was estimated by [ 3 H] thymidine incorporation. The antioxidant activity of the samples was verified by SNP and DPPH assays and the suppression of the iNOS protein expression was evaluated through Western blotting., Results: The HPLC-DAD-MS analysis of the Vd extract led to the identification of 5-methoxyluteolin-7-O-β-glucopyranoside (2), rutin (4) and the tannin galloyl-HHDP-glucopyranoside (3), besides the main flavonoid 3',5-dimethoxyluteolin-7-O-β-glucopyranoside (1), which was biologically evaluated in comparison with luteolin aglycone. The Vd extract, n-BuOH fraction and flavonoid 1 inhibited NO and TNF-α production by LPS-stimulated macrophages. The reduction of NO levels was mediated mainly by suppression of the iNOS expression. In addition, both the Vd extract (IC 50 13.6 µg/mL) and flavonoid 1 (IC 50 19.8 µg/mL; 41.6 µM) strongly inhibited stimulated lymphocyte proliferation when compared to the immunosuppressive agent cyclosporin A (IC 50 43.8 µg/mL; 36.4 µM). The Vd extract also showed a scavenging activity toward DPPH and NO free radicals. This is the first report describing the immunomodulatory potential of V. divergens and its major flavonoid (1)., Conclusion: Our findings showed that the aqueous leaf extract of V. divergens and its flavonoid reduced the production of excessive pro-inflammatory markers, collaborating with the Pantanal folk medicinal tradition that recommends the tea of cambará leaves for both asthma and flu. In addition, this study contributes to the knowledge of the pharmacological properties of 5-methoxy flavones, a poorly investigated subclass of flavonoids., (Copyright © 2018 Elsevier B.V. All rights reserved.)

Aims: To screen 20 micro-organisms for ω-transaminase (ω-TA) activity by the kinetic resolution of rac-1-phenylethylamine, followed by testing rac-amines of pharmaceutical interest with bulky substituents and to conduct the asymmetric synthesis of a chiral amine., Methods and Results: Stemphylium lycopersici was selected as the best biocatalyst. By the central composite rotatable design (CCRD), it was found that, at lower pH (5·5 and 6·5), the lyophilized micro-organism biocatalysed the kinetic resolution of rac-1-phenylethylamine with 99% enantiomeric excess (e.e.) ((R)-enantiomer) with acetophenone conversions ranged from 41 to 45%. Interestingly, the lyophilized crude enzymatic extract lead to better results at pH from 7·0 to 9·0, with conversions up to 47% and about 99% e.e. We also attested that as much as higher is the pyruvate (amino acceptor) concentration, higher is the acetophenone conversion, corroborating the presence of ω-TA-type enzymes. Among different sterically hindered racemic amines tested, rac-1,2,3,4-tetrahydro-1-naphthylamine and rac-phenylbutylamine were satisfactorily kinetically resolved in up to 91% e.e. (R). The results for the asymmetric synthesis showed excellent conversion (>85%) for the S-1-phenylethylamine, indicating (S)-stereopreference., Conclusion: Stemphylium lycopersici showed to be an important tool for broader substrate scope transaminases and a relevant player on the development of new biocatalysts with ability in asymmetric synthesis reactions., Significance and Impact of the Study: Here in, we contribute to the improvement of the biocatalytic toolbox for chiral amines synthesis. Interestingly, we have found that the crude enzymatic extract of the endophytic fungus S. lycopersici could accept bulky substrates with reasonable activity, compared to the wild-type transaminase already published over literature, and with high enantioselectivity., (© 2018 The Society for Applied Microbiology.)

Background: P. mucronata (Pm) comes from South America, Brazil and is characterized as "Maracujá de Restinga". It is used in folk medicine for its soothing properties and in treating insomnia., Objective: The present study for the first time analyzed the antioxidant and cytotoxicity of the hydroalcoholic leaves extract and fractions from Pm., Method: The cytotoxicity test will be evaluated by different assays (MTT and CV) against human prostate cancer (PC3) and mouse malignant melanoma (B16F10) cell lines, and the antioxidant test by DPPH method., Results: β-Amyrin, oleanolic acid, β-sitosterol and stigmasterol were isolated of the most active, hexane fraction. These substances were tested against the tumor cell lines: β-sitosterol and stigmasterol showed the most relevant activity to PC3 in CV assay and, oleanolic acid to B16F10 by the MTT assay. In addition, it was possible to indicate that the mode of cell death for stigmasterol, presumably is apoptosis. In terms of antioxidant activity, the hydroalcoholic leaves extract presented higher activity (EC50 133.3 µg/mL) compared to the flower (EC50 152.3 µg/mL) and fruit (EC50 207.9 µg/mL) extracts. By the HPLC-MS, it was possible to identify the presence of flavones in the leaf extract (isoschaftoside, schaftoside, isovitexin, vitexin, isoorientin, orientin)., Conclusions: P. mucronata hexane fraction showed promising cytotoxic effect against cancer cell lines, and stigmasterol contributes to this activity, inducing apoptosis of these cells. Furthermore, as other Passiflora species, Pm extract showed antioxidant activity and flavones are its major phenolic compounds., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.net.)

The aim of this research was to perform a phytochemical study of the methanol leaves extract of T. guianensis (MET) guided by vasodilatory and antioxidant activities. The chemical profile of MET and the ethyl acetate fraction (EA fraction) was determined by HPLC-UV-MS and EA fraction guided fractionation by reverse-phase chromatography. The vasorelaxant effects of MET, fractions, sub-fractions and constituents were assessed on rat aorta pre-contracted with phenylephrine. Antioxidant activity was evaluated by using a DPPH assay. The results show that MET-induced vasodilation was dependent on NO/cGMP; and that the PI3K/Akt pathway seems to be the main route involved in eNOS activation. The EA fraction showed greater vasodilatory and antioxidant potency and was submitted to further fractionation. This allowed the isolation and characterization of quercetin, quercetin 3- O -(6″- O -galloyl)-β-d-galactopyranoside and 1,4,6-tri- O -galloyl-β-d-glucose. Also, galloyl-HHDP-hexoside and myricetin deoxyhexoside were identified by HPLC-UV-MS. These compounds are being described for the first time for T. guianensis . 1,4,6-tri- O -galloyl-β-d-glucose and quercetin 3- O -(6″- O -galloyl)-β-d-galactopyranoside showed no vasodilatory activity. Quercetin and myricetin glycoside seems to contribute to the MET activity, since they have been reported as vasodilatory flavonoids. MET-induced vasodilation could contribute to the hypotensive effect of T. guianensis previously reported.

Natural products extracted from plants represent a valuable source of new bioactive substances. Many studies describe the potential of plant products for the treatment of cardiovascular diseases. Species of the Mandevilla genus have been studied for their biological activities, mainly as antioxidant, anti-inflammatory, and vasorelaxant. However, the phytochemical and pharmacological profiles of Mandevilla moricandiana have not been investigated yet. The aim of this study was to evaluate the vasodilator effect of the hydroalcoholic extract of the leaves of M. moricandiana , as well as its chemical profile. Chemical analysis and quantification of major compounds were performed by HPLC analysis. Total flavonoid content was quantified based on rutin equivalents, and major compounds were identified based on HPLC-DAD-MS analysis. M. moricandiana leaf extract-induced vasodilation was investigated in rat aortic rings precontracted with phenylephrine. The total flavonoids were quantified as 3.25 ± 0.11 % w/w of the hydroalcoholic leaf extract, and HPLC-DAD-MS allowed for the identification of luteolin and quercetin glycosides. The maximal relaxant effect of the hydroalcoholic leaf extract was 86.07 ± 1.68 % at a concentration of 30 µg/mL (p < 0.05; n = 6). The concentration of hydroalcoholic extract of the leaves of M. moricandiana necessary to reduce phenylephrine-induced contractions of the endothelium-intact aorta by 50 % was 0.82 ± 0.10 µg/mL. M. moricandiana leaf extract-induced vasodilation was abolished in aortas pretreated with NG-nitro-L-arginine methyl ester and 1H-[1,2,4]oxadiazolo-[4,3- α ]quinoxalin-1-one. In addition, diphenhydramine partially inhibited the effect of the hydroalcoholic extract of the leaves of M. moricandiana . Thus, M. moricandiana -induced relaxation depends on the endothelium and on the activation of the nitric oxide/cyclic GMP pathway, with the involvement of endothelial histamine H 1 receptors. Luteolin and quercetin glycosides seem to contribute to the extract activity., (Georg Thieme Verlag KG Stuttgart · New York.)

Background: Caries and periodontal diseases remain as important diseases in the Brazilian population. One important pathogen associated with this situation is Streptococcus mutans and other important factor is this pathogen's ability to adhere firmly to the tooth surface leading to dental biofilm formation and caries development., Objectives: Determine the antibacterial and other biological activities of P. venusta related to its potential to be used in the treatment of caries and periodontal disease., Methods: The growth inhibition by P. venusta of Streptococcus mutans, S. mitis, S. oralis and Candida albicans was determined using the broth microdilution method. In addition, the effect of the samples in adherence and reducing production of acids by S. mutans, and germ-tube formation of C. albicans was analysed. The Nitric Oxide (NO) production and cytotoxicity of P. venusta to peripheral blood mononuclear cells (PBMC) and RAW 264.7 Cell Line Murine Macrophage from Blood were assessed., Results: The crude extract (CE) and ethyl-acetate (AF) and n-butanol (BF) fractions showed antibacterial activity. The ethyl-acetate (AF) fraction showed the highest inhibition percentage against the adherence of S. mutans and C. albicans cells without budding, beyond NO production inhibition. There was not any cytotoxicity in the murine macrophages RAW 264.7 cells., Conclusion: Our results suggest that P. venusta presents potential to be used as a preliminary source of compounds that can provide helpful activity when used in prophylaxis or treatment of caries or periodontal disease., Summary: Biological activities of Pyrostegia venusta and its potential for use in formulations for the prevention of oral diseases. Abbreviations used: NO: Nitric oxide, PBMC: Peripheral blood mononuclear cells, CE: Crude extract, AF: Ethyl-acetate fraction, BF: n-butanol fraction, HF: Hexane fraction, WF: Water fraction, MIC: Minimum inhibitory concentration, MBC: Minimum bactericidal concentration, ATCC: American Type Culture Collection, CFU: Colony-forming units, BHI: Brain heart infusion, RPMI: Roswell Park Memorial Institute, MOPS: 3-(N-morpholino)propanesulfonic acid, DMEM: Dulbecco's modified Eagle's médium, LPS: Lipopolysacharide, MTT: 3-(4,5-Dimethylthiazol-2-yl)-2,5-Diphenyltetrazolium Bromide, OD: Optical density, AC: Acteoside.

Background: Red algae of the genus Laurencia J. V. Lamouroux are a rich source of secondary metabolites with important pharmacological activities such as anti-tumoral, anti-inflammatory, anti-fungal, anti-viral, anti-leishmanial, anti-helminthic, anti-malarial, anti-trypanosomal, anti-microbial as well as anti-bacterial against Mycobacterium tuberculosis., Objective: In the present study, we evaluated the inhibition of nitric oxide (NO) and tumor necrosis factor-α production and the anti-mycobacterial activity of crude extracts from the red Alga Laurencia dendroidea (from the South-Eastern coast of Brazil). Halogenated sesquiterpenes elatol (1), obtusol (2) and cartilagineol (3), previously isolated from this Alga by our group, were also studied., Materials and Methods: The lipopolysaccharide-activated macrophage cells (RAW 264.7) were used as inflammation model. Cytotoxic effect was determined using a commercial lactate dehydrogenase (LDH) kit and 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay. The growing Mycobacterium inhibition was verified against Mycobacterium bovis Bacillus Calmette-Guérin and M. tuberculosis H37 Rv strains., Results: The crude extract from Alga collected at Angra dos Reis, RJ, Brazil, was the most active inhibitor of both mycobacterial growth (half maximal inhibitory concentration [IC50] 8.7 ± 1.4 μg/mL) and NO production by activated macrophages (IC50 5.3 ± 1.3 μg/mL). The assays with isolated compounds revealed the anti-mycobacterial activity of obtusol (2), whereas (-)-elatol (1) inhibited the release of inflammatory mediators, especially NO. To our knowledge, this is the first report describing an anti-mycobacterial effect of L. dendroidea extract and demonstrating the association of this activity with obtusol (2)., Conclusion: The described effects of active compounds from L. dendroidea are promising for the control of inflammation in infectious diseases and specifically, against mycobacterial infections associated with exacerbated inflammation., Summary: Inflammation is strongly involved in the pathogenesis of most infectious diseases, including TB. The treatment of TB is based on the use of anti mycobacterial drugs, however the most severe forms of TB, require additional anti inflammatory therapy to prevent excessive inflammation. A combination of these properties in one compound could provide additional therapeutic benefits. In this work, we studied L. dendroidea extracts and purified compounds and demonstrated that the LDA extract and (-)-elatol (1) were potent in inhibiting NO production by macrophages through the specific inhibition of iNOS expression. The LDA and LDM extracts and obtusol (2) were active against virulent strain of M. tuberculosis. This is the first report demonstrating that the anti-inflammatory activities of L. dendroidea were associated with the presence of (-)-elatol (1), whereas anti-mycobacterial activities of L. dendroidea extracts were associated with obtusol (2).

Ultraviolet-B radiation is an important abiotic factor that can stimulate the production of secondary metabolites, including polyphenolic compounds. Kalanchoe pinnata (Crassulaceae) is a medicinal plant popularly used in Brazil for treating wounds and inflammation. This species is rich in phenolic compounds, which could account for some of its biological activities, including antileishmanial, antihypertensive and antibacterial properties. We investigated the effects of supplemental UV-B radiation on the phenolic profile, antioxidant activity and total flavonoid content of leaves of K. pinnata. Plants were grown under white light (W - control) and supplemental UV-B radiation (W+UVB). Supplemental UV-B radiation enhanced the total flavonoid content of the leaf extracts, without affecting the antioxidant activity or yield of extracts. Analysis by TLC and HPLC of W and W+UVB leaf extracts revealed quantitative and qualitative differences in their phenolic profiles. W+UVB extracts contained a higher diversity of phenolic compounds and a larger amount of quercitrin, an important bioactive flavonoid of this species. This is the first report of the use of ImageJ® program to analyze a TLC visualized by spraying with NP-PEG reagent. UV-B radiation is proposed as a supplemental light source in K. pinnata cultivation in order to improve its flavonoid composition., (Copyright © 2015 Elsevier B.V. All rights reserved.)

Tuberculosis (TB) remains a serious public health problem aggravated by the emergence of M. tuberculosis (Mtb) strains resistant to multiple drugs (MDR). Delay in TB treatment, common in the MDR-TB cases, can lead to deleterious life-threatening inflammation in susceptible hyper-reactive individuals, encouraging the discovery of new anti-Mtb drugs and the use of adjunctive therapy based on anti-inflammatory interventions. In this study, a series of forty synthetic chalcones was evaluated in vitro for their anti-inflammatory and antimycobacterial properties and in silico for pharmacokinetic parameters. Seven compounds strongly inhibited NO and PGE2 production by LPS-stimulated macrophages through the specific inhibition of iNOS and COX-2 expression, respectively, with compounds 4 and 5 standing out in this respect. Four of the seven most active compounds were able to inhibit production of TNF-α and IL-1β. Chalcones that were not toxic to cultured macrophages were tested for antimycobacterial activity. Eight compounds were able to inhibit growth of the M. bovis BCG and Mtb H37Rv strains in bacterial cultures and in infected macrophages. Four of them, including compounds 4 and 5, were active against a hypervirulent clinical Mtb isolate as well. In silico analysis of ADMET properties showed that the evaluated chalcones displayed satisfactory pharmacokinetic parameters. In conclusion, the obtained data demonstrate that at least two of the studied chalcones, compounds 4 and 5, are promising antimycobacterial and anti-inflammatory agents, especially focusing on an anti-tuberculosis dual treatment approach.

The genus Ocotea (Lauraceae) is distributed mainly in tropical and subtropical regions. Some species of this genus as O. puberula and O. quixos have been described in the literature, showing antibacterial activity. And Ocotea macrophylla showed anti-inflammatory activity with inhibition of COX-1, COX-2, and LOX-5. The purpose of this study was the phytochemical investigation of the plant species Ocotea notata from Restinga Jurubatiba National Park, Macaé, RJ, Brazil, and the search for antimycobacterial fractions and compounds. The crude extract was evaluated for antimycobacterial activity and presented 95.75 ± 2.53% of growth inhibition at 100 µg/mL. Then, it was subjected to a liquid-liquid partition and subsequently was chemically investigated by HPLC, revealing the major presence of flavonoids. In this process the partition fractions hexane, ethyl acetate, and butanol are shown to be promising in the antimycobacterial assay. In addition, ethyl acetate fraction was chromatographed and afforded two flavonoids identified by MS and NMR as afzelin and isoquercitrin. The isolated flavonoids afzelin and isoquercitrin were evaluated for their antimycobacterial activity and for their ability to inhibit NO production by macrophages stimulated by LPS; both flavonoids isoquercitrin (Acet22) and afzelin (Acet32) were able to inhibit the production of NO by macrophages. The calculated IC50 of Acet22 and Acet32 was 1.03 and 0.85 µg/mL, respectively.

Two new chamigrane sesquiterpenes 1-2 and three known compounds 3-5 were isolated from a lipophilic extract of the red alga Laurencia dendroidea collected from the Southeastern Brazilian coast. Dendroidone (1) and dendroidiol (2) were isolated from samples collected at Biscaia Inlet, Angra dos Reis, Rio de Janeiro and at Manguinhos Beach, Serra, Espírito Santo, respectively. Debromoelatol (3), obtusane (4) and (1S*,2S*,3S*,5S*,8S*,9S*)-2,3,5,9-tetramethyltricyclo[6.3.0.0¹·⁵]undecan-2-ol (5) were obtained from specimens collected at Vermelha Beach, Parati, Rio de Janeiro. The structures of new compounds were elucidated by extensive NMR (¹H-, ¹³C-, COSY, HSQC, HMBC and NOESY) and high resolution mass spectrometry analysis. Additionally, the absolute configuration of compound 2 was assigned by X-ray analysis. Full spectroscopic data is described for the first time for compound 3. Anti-inflammatory and antimycobacterial activities of compounds 2-5 were evaluated. Compounds 3-5 inhibited the release of inflammatory mediator NO while TNF-α levels were only affected by 3. All compounds tested displayed moderate antimycobacterial action.

Introduction: Influenza viruses are common agents of flu outbreaks, epidemics, and pandemics that have occurred through the centuries. Prevention and control of flu are of great clinical importance, since they cause serious damage to health, with a consequent impact on quality of life and economy of a country. Resistance against the current drugs justifies the development of new anti-influenza molecules. Flavonoids exhibit significant activity against flu through their anti-inflammatory and antiviral properties. The profile of these molecules makes them particularly promising as therapeutic agents against flu., Areas Covered: This review focus on the activity of flavonoids on different influenza virus targets as well as their use in patented pharmaceutical formulations. Twenty-one patents of these compounds for prophylaxis and treatment of influenza infection are discussed., Expert Opinion: The H1N1 influenza pandemic in 2009 resulted in a significant increase in the number of patents claiming pharmaceutical formulations for prophylaxis and treatment of flu. The research advances on flavonoids showing anti-influenza activity and the efforts made by researchers and industries consolidate the interest on new alternatives for the therapy of an infectious disease that represents a serious public health problem throughout the world.

The chemical composition and immunosuppressive potential of the flowers from Kalanchoe pinnata (Crassulaceae) were investigated. We found that the aqueous flower extract was more active than the leaf extract in inhibiting murine T cell mitogenesis in vitro. Flavonoids isolated from the flower extract were identified and quantitated based on NMR and HPLC-DAD-MS analysis, respectively. Along with quercetin, four quercetin glycosyl conjugates were obtained, including quercetin 3-O-beta-D-glucuronopyranoside and quercetin 3-O-beta-D-glucopyranoside, which are described for the first time in K. pinnata. All flavonoids inhibited murine T cell mitogenesis and IL-2 and IL-4 production without cell toxicity. This is the first report on the pharmacological activity of flowers of a Kalanchoe species, which are not used for curative purposes. Our findings show that K. pinnata flowers are a rich source of T-suppressive flavonoids that may be therapeutically useful against inflammatory diseases.

Ten Psychotria species were collected in two fragments of Atlantic Forest in Rio de Janeiro: Psychotria pubigera (P1A and B), P. ruelliifolia (P2), P. suterela (P3), P. stachyoides (P4), P. capitata (P5), P. glaziovii (P6), P. leiocarpa (P7), P. nuda (P8), P. racemosa (P9) and P. vellosiana (P10). Ethanol extracts of these species were evaluated for their antimycobacterial activity, in an attempt to find new antituberculosis agents. Psychotria pubigera (P1A), P. ruelliifolia (P2) and P. stachyoides (P4) were the most active against Mycobacterium. The anti-inflammatory potential of these extracts was also evaluated in vitro to learn if they inhibit nitric oxide (NO) production in macrophages and if they have free-radical scavenging properties, because inflammation is a severe problem caused by tuberculosis, especially when the infection is from M. bovis or M. tuberculosis. Psychotria suterela (P3), P. stachyoides (P4) and P. capitata (P5) were the most active in inhibiting macrophage NO production but they were not the most antioxidant species. This suggests that NO inhibitory activity is not due to the scavenging of NO generated but due to a specific inhibition of iNOS activity or expression. In addition, cytotoxicity was tested in the macrophages (the host cells of the Mycobacterium) and it was verified that the extracts selectively killed the bacteria and not the host cells. When analyzing antimycobacterial, cytotoxicity and NO inhibitory activities in combination, P. stachyoides (P4) was the most promising anti-TB extract tested. Further, indol alkaloids were detected in P. suterela and P. nuda, and 5,6-dihydro-β-carboline alkaloids in all of the species studied, with the highest amounts found in P. capitata and P. racemosa., (© Georg Thieme Verlag KG Stuttgart · New York.)

Ethnopharmacological Relevance: Leaves from Kalanchoe pinnata (Lamarck) Persoon (Crassulaceae) are popularly used for healing wounds. Its antileishmanial properties are established in experimental animals, and its active flavonoid components have been identified., Aim of the Study: In this study, we attempted to standardize the extract from K. pinnata leaves by evaluating the influence of season of harvest, sunlight exposure and method of extraction on antileishmanial flavonoids content., Materials and Methods: HPLC-DAD-MS was used to identify and quantify the active antileishmanial flavonoids in different extracts. ANOVA test for analyses of variance followed by the Tukey test of multiple comparisons were used in the statistical analysis. The antileishmanial potential was assessed by the activation of nitric oxide production by murine macrophage using the Griess method., Results: We demonstrated that active flavonoids were significantly more abundant when the leaves were collected in the summer, and that aqueous extraction at 50°C allowed the highest flavonoid extraction. The benefit of sunlight exposure was confirmed in plants cultivated under direct sunlight when compared with those that grown under shade. Under sunny conditions the yield of the most active antileishmanial favonoid quercitrin was increased by 7-fold. All aqueous extracts tested were capable to enhance the macrophage nitric oxide production. However, hot aqueous extract from leaves collected in summer exhibited the higher activity, in agreement with HPLC-DAD-MS analysis tendency. In addition, with the aim of reducing the individual chemical variations of the plant constituents and optimizing the production of the active extract, it was obtained in vitro monoclonal KP specimens that were easily adapted to field conditions and were able to produce antileishmanial flavonoids., Conclusion: Our study reports the better conditions of cultivation, harvest and extraction protocol for obtaining a K. pinnata extract exhibiting the highest antileishmanial activity. Additionally, we propose the flavonoids quercetin 3-O-α-L-arabinopyranosyl (1→2)-α-L-rhamnopyranoside and quercitrin, as satisfactory chemical markers for standardization purposes., (Copyright © 2010 Elsevier Ireland Ltd. All rights reserved.)

Previously, we described the protective action of the immunomodulatory extract of Kalanchoe pinnata (Kp) in murine and human cutaneous leishmaniasis. In the present study, we investigated the effectiveness of Kp against visceral leishmaniasis, using the BALB/c mouse model of infection with Leishmania chagasi. Mice receiving oral daily doses of Kp (400 mg/kg) for 30 days displayed significantly reduced hepatic and splenic parasite burden, when compared with untreated animals. Protectiveness was accompanied by a reduction in parasite-specific IgG serum levels, and impaired capacity of spleen cells to produce IL-4, but not IFN-gamma and nitric oxide upon antigen recall in vitro. The reference drug Pentostam (72 mg/kg) given by the intra-peritoneal route on alternate days produced an anti-leishmanial effect similar to oral Kp. Our findings show that the oral efficacy of Kp, seen previously in murine cutaneous leishmaniasis, extends also to visceral leishmaniasis caused by L. chagasi, a difficult to treat and lethal disease of man.

Leishmaniasis is a parasitic disease that threatens 350 million people worldwide. In a search for new antileishmanial drugs, the in vitro activity of flavonoids from Kalanchoe pinnata (Crassulaceae) was previously demonstrated in infected cells. In order to demonstrate the safety and oral activity of K. pinnata, flavonoids were evaluated in vivo in a murine model of cutaneous leishmaniasis. Daily oral doses of quercetin 3-O-alpha-L-arabinopyranosyl (1-->2)-alpha-L-rhamnopyranoside, quercetin 3-O-alpha-L-rhamnopyranoside, and free quercetin (16 mg/kg body weight) all were able to control the lesion growth caused by Leishmania amazonensis and to significantly reduce parasite load. These flavonoids were as effective as the crude K. pinnata aqueous extract given at 320 mg/kg body weight. HPLC-DAD-MS analysis of the plasma of extract-treated mice suggested that quercetin and quercetin glucuronides are the main metabolites of K. pinnata quercetin glycosides. Our results indicate that K. pinnata quercetin glycosides are important active components of the aqueous extract and that they possess potent oral efficacy against cutaneous leishmaniasis.

In the present study a family of macrocyclic and acyclic analogues as well as seco-analogues of avermectins were prepared from commercial Ivermectin (IVM) and their antileishmanial activity assayed against axenic promastigote and intracellular amastigote forms of Leishmania amazonensis. Contrarily to the filaricidal activity, the leishmanicidal potentiality of avermectin analogues does not appear to depend on the integrity of the non-conjugated Delta(3,4)-hexahydrobenzofuran moiety. Conjugated Delta(2,3)-IVM or its corresponding conjugated secoester show higher anti-leishmania activity than the parent compound. Surprisingly, the diglycosylated northern sub-unit exhibits the same anti-amastigote potentiality as the southern hexahydrobenzofuran. As expected for compounds derived from the widely used Ivermectin antibiotic, little toxicity has been noticed for most of the novel analogues prepared.

Previously, we reported the immunosuppressive action of the aqueous extract of Kalanchoe pinnata (Kp) in mice. In the present study, we report on the protective effect of Kp in fatal anaphylactic shock, likewise a Th2-driven immunopathology, and the identification of its active component. Mice daily treated with oral Kp during hypersensitization with ovalbumin were all protected against death when challenged with the allergen, as compared with the 100% mortality in the untreated group. A single intraperitoneal dose 3 h prior to challenge was partially effective. Oral protection was accompanied by a reduced production of OVA-specific IgE antibodies, reduced eosinophilia, and impaired production of the IL-5, IL-10 and TNF-alpha cytokines. In vitro, Kp prevented antigen-induced mast cell degranulation and histamine release. Oral treatment with the quercitrin flavonoid isolated from Kp prevented fatal anaphylaxis in 75% of the animals. These findings indicate that oral treatment with Kp effectively downmodulates pro-anaphylactic inducing immune responses. Protection achieved with quercitrin, although not maximal, suggests that this flavonoid is a critical component of Kp extract against this extreme allergic reaction.

Sixteen not new aromatic compounds were prepared by one-pot reaction i.e. through Baylis-Hillman reaction and were the first time evaluated against promastigote Leishmania amazonensis and infected mammalian cells. Most of the compounds were selectively more active against amastigotes than the reference drug sodium stibogluconate (Pentostam, IC(50)=44.7 microM). We found that 3-hydroxy-2-methylene-3-(4-bromophenyl) propanenitrile (13) was the most active (IC(50)=12.5 microM) and safer compound (0.0 (0.9); % macrophage LDH release), being the lead compound.

The importance of flavonoids for the antileishmanial activity of Kalanchoe pinnata was previously demonstrated by the isolation of quercitrin, a potent antileishmanial flavonoid. In the present study, the aqueous leaf extract from the medicinal plant K. pinnata (Crassulaceae) afforded a kaempferol di-glycoside, named kapinnatoside, identified as kaempferol 3-O-alpha-L-arabinopyranosyl (1-->2) alpha-L-rhamnopyranoside (1). In addition, two unusual flavonol and flavone glycosides already reported, quercetin 3-O-alpha-L-arabinopyranosyl (1-->2) alpha-L-rhamnopyranoside (2) and 4',5-dihydroxy-3',8-dimethoxyflavone 7-O-beta-D-glucopyranoside (3), have been isolated. Their structures were determined via analyses of mono and bi-dimensional (1)H and (13)C NMR spectroscopic experiments and HR-MALDI mass spectra. Because of its restricted occurrence and its abundance in K. pinnata, flavonoid (2) may be a chemical marker for this plant species of high therapeutic potential. The three flavonoids were tested separately against Leishmania amazonenis amastigotes in comparison with quercitrin, quercetin and afzelin. The quercetin aglycone - type structure, as well as a rhamnosyl unit linked at C-3, seem to be important for antileishmanial activity.

The fresh juice from leaves of Sedum dendroideum Moc & Sessé (Crassulaceae) is used in Brazilian traditional medicine for the treatment of gastric and inflammatory disorders. The present investigation was carried out to evaluate in vivo antinociceptive and anti-inflammatory activities of this plant material. The oral administration (0.1-1g/kg) of the lyophilized Sedum dendroideum juice (L J) caused a significant dose-related reduction of acetic acid-induced writhing response (ID(50)=631 mg/kg) and inhibited croton oil-induced ear oedema formation (66% inhibition at 1g/kg) in mice. In the formalin-induced nociception in mice, L J (1g/kg) only inhibited the second phase of nociception (46%). Phytochemical investigation revealed four known kaempferol glycosides, here, described at the first time for this species. These flavonoids probably explain the antinociceptive and anti-inflammatory effects of the fresh juice of Sedum dendroideum.

The infusion of aerial parts (EI) of Eleusine indica Gaertn (Poaceae) is used in Brazil against airway inflammatory processes like influenza and pneumonia. Pre-treatment with 400 mg/kg of crude extract inhibited 98% of lung neutrophil recruitment in mice exposed to aerosols of lipopolysaccharide (LPS) from Gram-negative bacteria, in a dose-dependent manner. At 400 microg/kg, schaftoside (6-C-beta-glucopyranosyl-8-C-alpha-arabinopyranosylapigenin) and vitexin (8-C-beta-glucopyranosylapigenin), isolated from EI, inhibited 62% and 80% of lung neutrophil influx, respectively. These results may justify the popular use of E. indica against airway inflammatory processes.